1. Field
The present invention relates to improvements in thermally actuated valves of a type capable of selectively connecting one or the other of a pair of ports with a common port in accordance with temperature.
2. Prior Art
Ported switching valves are known in which a wax pellet type sensor is arranged to extend through a bulkhead for sensing a temperature condition and to operate a plunger which moves a valve element between a pair of seats for selecting a port in accordance with the sensed temperature. Such valves are subject to the objection that the valve element may remain out of contact with both seats for an interval while the pellet material undergoes a change of state. It is known to employ snap action bimetal discs in ported switching valves, however, such discs are often influenced by various temperatures other than the temperature desired to be sensed as a result of its location adjacent other components of the valve assembly which may be heated or cooled by conditions other than the sensed condition.